Maternal allele mutation: Slippage synthesis furnishing evolutionary trend

Anand Kumar Anand Kumar,Rk Kumawat Rk Kumawat,Ginni Kumawat Ginni Kumawat,Rajesh Kumar Rajesh Kumar

doi:10.30574/gscbps.2021.14.1.0011

Abstract

Gain or loss of repeat motifs leads to an allelic mismatch in the disputed child which is a deviation from the Mendelian inheritance, thereby leading to a paternal mismatch of putative father or exclusion of mother in case of maternal allelic mismatch. This allelic mismatch at one or more loci is a major cause of forensic inferences. The biological samples of the case were genotyped using Powerplex®- Fusion 5C system kit and Investigator® Argus X-12 QS kit as per recommendations of the manufacturer. In this case, identification of a putrefied dead body with 22 autosomal STR loci, primarily analyzed by Powerplex®- Fusion 5C system kit divulged a maternal mismatch at locus D13S317. Alleles at the locus D13S317 allegedly belonging to the father of the deceased and the mother were observed as 10/11, 11/11 and 10/10 respectively. To rule out allelic mismatch at this particular locus, 12 X-STR loci were amplified, in which all the maternal alleles of deceased completely matched with the mother. This case study indicates the extension of one microsatellite repeat motif (TATC) at locus D13S317 in the population of Rajasthan. The reported mutation rate was 0.14% and 0.04% at locus D13S317 in paternal and maternal meiosis respectively.

Highlights

Rajasthan is situated in the North-western region of India
Amplification of the 22 autosomal STRs along with Amelogenin was performed by using PowerPlex® Fusion 5C system kit (Promega) and 12 X-STR markers (DXS10103, DXS8378, DXS10101, DXS10134, DXS10074, DXS7132, DXS10135, DXS7423, DXS10146, DXS10079, HPRTB and DXS10148) Investigator® Argus X-12 QS Kit (19300 Germantown Road Germantown, MD 20874) on ABI Thermal cycler 9700 (Thermo) as per the prescribed protocol of the manufacturer except for the half-reaction volumes
In the case of the girl child, X-STR amplification kit is required for exploration and Y-STR amplification kit cannot be used to resolve the maternal mismatch in this case

Summary

Introduction

Rajasthan is situated in the North-western region of India. Microsatellite mutation at the STR locus D13S317 has not been reported in the population of Rajasthan so far. This case report marks a breakthrough in the observation of microsatellite mutation in the studied population. Genetic diversity including autosomal and Y-STRs on the population of Rajasthan is well established by some authors [2], [3], [4]. Indian sequencing datasets are underreported globally India has 17% of the world population having extensive genetic diversity so it is very important to report any microsatellite mutations in the Indian scenario

Methods

Results

Conclusion